Growth Formation Research Articles

Widely acclaimed but poorly named: Phylogeny and systematics of the African daisy genus Dimorphotheca (Asteraceae, Calenduleae)

AbstractPhylogenetic relationships in the South African daisy genus Dimorphotheca have long been uncertain, with the taxonomy of the genus relying on a few morphological traits, most prominently capitulum sexual system (e.g., cypsela type) and ray colour, which may not be evolutionarily conserved. Here we present the first well‐sampled molecular phylogeny of Dimorphotheca, based on nuclear ribosomal (ITS, ETS) and plastid trnL‐trnF region DNA sequences from multiple accessions per species. Although the relationships suggested by these markers are broadly congruent, we do find some instances of incongruence which we resolve using a combined decomposition and deletion approach. Using our best estimate of phylogenetic relationships, we reconstruct the evolution of capitulum fertility and ray colour to assess the evolutionary conservatism of these traits and their taxonomic utility. We find support for the monophyly of Dimorphotheca, excluding the recently segregated Osteospermum polypterum, and our data thus support the modern, enlarged circumscription of the genus incorporating the former genus Castalis and Osteospermum sect. Acanthotheca and O. sect. Blaxium. Major subclades within Dimorphotheca are largely cohesive in terms of geographic distribution and morphological traits such as growth form and cypsela structure. While many species are resolved as monophyletic, the polyphyly of a few species suggests a need for taxonomic re‐evaluation. On the basis of both morphological and molecular data, we describe one new species, and elevate one variety to species level. A full taxonomic key to the enlarged genus is presented for the first time. Ancestral reconstructions show that capitulum sexual system and ray lamina colour are not evolutionarily conserved and that neither can therefore be used to delimit major lineages within Dimorphotheca. While our findings resolve some taxonomic problems, they also highlight the need for further species‐level taxonomic work on Dimorphotheca.

The Influence of Digital Economic Growth and Productive Work Force Toward Human Development Index in Indonesia Viewed from a Maqashid Sharia Perspective

Introduction: Community productivity is critical in maintaining quality of life to avoid disasters. The use of digital technology in the economic aspect has also provided opportunities for people far from the market to earn income to meet their living needs. Objective: The research problem is formulated as follows: What is the influence of digital economic growth and productive labor on the Human Development Index in Indonesia in 2018-2022, both partially and simultaneously, and how is this viewed from a maqasid syariah perspective?Method: This research is presented as five-year time series data and analyzed using quantitative descriptive methods and multiple linear regression analysis, using Eviews 10 as an analytical tool. The sampling technique used was purposive sampling, with sample criteria in the form of digital economic growth, productive workforce, and data during the 2018-2022 period. Result: The digital economic growth variable partially has a negative and insignificant effect on the Human Development Index. Meanwhile, the productive labor variable positively and significantly affects the Human Development Index. Simultaneously, the growth of the digital economy and productive workforce has had a positive and significant effect on the Human Development Index in Indonesia in 2018-2022. From a maqasid syariah perspective, digital economic activities are permitted if no arguments prohibit them. Implication: This research provides valuable insights that can influence how we view and approach digital economic growth and productive labor in Indonesia's human development context. By considering these impacts, various parties can optimize their strategies to advance people's quality of life more effectively.

A Floristic Study of Aquatic and Wetland Plants of Lal Nalla Dam of Samadrapur Tehsil, District Wardha, Maharashtra

The floristic diversity studywas carried out at Lal Nalla Dam. It was constructed on the Lal Nalla River, the nearest city to the dam is Samudrapur in Wardha District of Maharashtra. Extensive and repeated field surveys were carried out from January 2020 to December 2021 in the study area, covering all the seasons of the year to document the species richness of the wetland. The three sites were selected from where a comprehensive list of aquatic and wetland plants occurring in the study areais prepared. During field surveys, emphasis was given to document the type of vegetation, growth form, and associated species. Morphological characters were recorded based on fresh material in the field. The open water zone of the lake has less growth of submerged and free-floating plants. The Marginal shallow zone with a depth of 30-40 cm is inhibited by the floating-leaved-like and emergent plants. In the study area total of 41 species were investigated from three major habitats as open-water zone, marginal shallow zone, and seasonal puddles were studied and according to the sites, the growth formlike one floating-leaved,five submerged plants, twenty-nine emergent, and six other plants was identified belonging to 22 different families in which Cyperaceae was a dominant family with 6 species. The study area shows species diversity but because of seasonal water level change and grazing by domestic livestock the disturbance is seen in vegetation.

Adversity and Resiliency: Athlete Experiences within U.S. College Sport

Research regarding the benefits and detriments of the U.S. collegiate sport governance structure are mixed. Guided by Richardson’s Resiliency Theory (2002), former athletes (n = 215) revealed specific themes of adversity experienced during college with the most prevalent including injury, time demands, and coach-athlete tension. Through interview, athletes noted adversity promoted their resiliency, facilitated grit/perseverance, enhanced teamwork and time management skills, and led to other forms of growth. This study extends our understanding of the long-term impacts of competitive sport participation in this context. This understanding is important for administrators seeking to maximize participant experiences and emulate, enhance, or reform the U.S. College Sport governance model.

Involvement of Academic Staff in the Practice of Professional Development

The article explores the level of involvement of scientific and pedagogical professionals in various social activities for professional development compared to other employee groups. It argues that obtaining additional professional training can be a valuable tool for career growth. The author sees professional development as an integral part of academic growth for scientific and educational workers, along with personal and career development. The findings are based on a combination of theoretical and empirical research conducted by domestic and international scholars, as well as official statistical data and the results of an original sociological study. The study involved a questionnaire survey of scientific and educational professionals (n = 223), as well as other employee groups (n = 833), in the Tyumen and Sverdlovsk regions. As a result, it was found that scientific and pedagogical workers are more likely to engage in professional development activities compared to other categories of the employed population. Continuing professional education programs appear to be the most common form of professional growth. Due to their specialized activities, academic staff tend to develop digital skills more often, while other groups develop personal skills to a greater degree. Based on the level of involvement in professional development, we identified five groups of respondents: “active and engaged”, “achieving the desired level or feeling disappointed”, “questioning or confused”, “recognizing the importance of professional development”, and “rejecting professional development”. The theoretical and empirical findings led to the development of potential strategies to enhance the engagement of scientific and educational professionals in ongoing skill development and acquisition of new competencies. This article is aimed at university management responsible for professional development of academic staff. The findings presented here may have practical implications for the development of personnel strategies at universities with the goal of increasing human capital and professional competence among academic staff, as well as motivating them to engage in continuous learning. The results of this study could be beneficial for participants in the academic community, as well as for specialists involved in developing educational programs and planning the future of universities strategically. The material presented in this paper is relevant not only for academic staff, but also for graduate students who are focused on their continuous professional growth within the academic sector.

New insights into a sensitive life stage: hydraulics of tree seedlings in their first growing season.

The first year in a tree's life is characterized by distinct morphological changes, requiring constant adjustments of the hydraulic system. Despite their importance for the natural regeneration of forests and future vegetation composition, little has been known about the hydraulics of tree seedlings. At different times across the first growing season, we analysed xylem area-specific (Kshoot_Axyl) and leaf area-specific (Kshoot_L) shoot hydraulic conductance, as well as embolism resistance of three temperate conifer trees, two angiosperm trees and one angiosperm shrub, and related findings to cell osmotic parameters and xylem anatomical traits. Over the first 10 wk after germination, Kshoot_Axyl and Kshoot_L sharply decreased, then remained stable until the end of the growing season. Embolism resistance was remarkably low in the youngest stages but, coupled with an increase in cell wall reinforcement, significantly increased towards autumn. Contemporaneously, water potential at turgor loss and osmotic potential at saturation decreased. Independent of lineage, species and growth form, the transition from primary to secondary xylem resulted in a less efficient but increasingly more embolism-resistant hydraulic system, enabling stable water supply under increasing risk for low water potentials.

Botanical origins of honeys from pollen analysis during the main honey flow across agro-ecologies in kelala district, South Wollo, Ethiopia

This study aimed to identify the botanical origins of honey through pollen analysis across agro-ecologies of Kelala district, South Wollo, Ethiopia. Fifteen honey samples were collected from traditional beehives, with 5 samples from each of the highland, midland, and lowland agro-ecologies. Qualitative and quantitative pollen analyses revealed that 22 honeybee plants belonging to 8 families, with no families of poisonous origin, and 3 growth forms were identified. Among these plant species, 18 were found in the midland and 13 were recorded in each of the highland and lowland agro-ecologies. The family Fabaceae, with 7 (31.81 %) of the identified honeybee plants, was highly dominant (p < 0.03) compared to the other families. Herbs, with 18 plant species, were highly dominant (p < 0.001) compared to shrubs and trees. In terms of plant species diversity, 10 plant species (Bidens pachyloma, Guizotia scabra, Becium grandiflorum, Eleusine floccifolia, Lens culinaris, Lippia adoensis, Medicago polymorpha, Ocimum basilicum, Trifolium steudneri, and Zea mays) were found in more than 50 % of the honey samples, with the first 2 in all the samples studied. Analysis of each honey sample showed that 8 (53.33 %) of the samples were monofloral, 3 (20 %) were bifloral, and the rest were multifloral. However, all the honeys produced due to agro-ecology (geographical origin) were monofloral. Guizotia scabra in the highland and Bidens pachyloma in the midland and lowland agro-ecologies were the predominant pollen producing species and contributors of monofloral honey. In conclusion, the safe and healthy monofloral honey produced across agro-ecologies suggests the suitability of the honey for human consumption and can potentially attract investors.

Relating ten years of rock temperature monitoring to rockwall weathering processes in steep mountain valleys in western Norway

Most existing studies on rockwall frost regimes and frost weathering at rockwalls focus on permafrost-affected rockwalls. However, a high share of rockwall surface areas in Norway and in many other cold-climate environments is actually free of permafrost. It is therefore of interest how these permafrost-free rockwall systems will respond to future changes in air and rock temperatures. In this study, we report field measurements conducted at rockwalls beneath the current permafrost limit and investigate thermal regimes at rockwalls that include both rockwall areas with and without permafrost. We present a unique dataset of up to ten years of rockwall temperature measurements from ten temperatures sensors installed in two mountain valleys in western Norway. An analysis of the different rockwall thermal regimes with respect to rock weathering and associated rockfall supply for both, permafrost-affected and permafrost-free rockwalls is provided. The highest intensity of recent rockwall weathering including determined rockwall retreat rates and associated rockfall supply is detected for northeast-facing rockwalls followed by south-facing rockwalls in our study area. Frost cracking activity, probably in the form of segregation ice growth, seems to be an important factor particularly for the high weathering intensity on northeast-facing rockwalls whereas solar radiation-induced thermal stresses, which favour incremental subcritical crack growth, is assumed to play a relevant role in the moderate weathering intensity on south- and southwest-facing rockwalls. A mean annual and study area-wide rockwall retreat rate of 0.24 mm yr−1 is estimated for our ten-year investigation period (2010−2020) which is comparable to other published rates in similar lithologies and climates. As it can be assumed that seasonal frost regimes and permafrost will react differently to ongoing and future climate changes, more attention should be paid to analyse these two different thermal regimes with respect to possible varied implications for mechanical rockwall weathering and associated rockfall supply.

Growth form variations of Amaranthus hybridus L. biotypes with EPSPS mutations

AbstractSeveral Amaranthus hybridus L. biotypes present single and triple amino acid substitutions in EPSPS (5‐enolypyruvylshikimate‐3‐phosphate synthase). In resistant and tolerant species to glyphosate, differential susceptibility and alterations in the EPSPS sequence could cause modifications in their morphological–structural characteristics, an issue that is unknown for biotypes of A. hybridus. The aim of the work was to determine the susceptibility to glyphosate, the presence of mutations in EPSPS and the growth form in four biotypes of this weed from north‐central Argentina. To carry out this, a dose–response assay was conducted, to determine the presence of mutations in the EPSPS, DNA was extracted, amplified and sequenced, and finally, to evaluate the morphological–structural variations, the growth form was analysed. Our findings revealed that Ah03, Ah07 and Ah36 biotypes had resistance factors of 22 to 118. The EPSPS sequence remains unaltered in the Ah39 biotype, leading it to be considered a susceptible biotype. Biotypes Ah03 and Ah36 had heterozygous changes in the DNA sequence resulting in amino acid substitutions at positions 102, 103 and 106 being considered resistant biotypes, whereas in Ah07 some individuals showed unaltered DNA sequences and others exhibited heterozygous changes. The growth form was quantitatively different between biotypes, standing the most susceptible biotype that produced more seeds and required less thermal time for the appearance of the terminal inflorescence. The present investigation provides new evidence that resistant biotypes with the triple DNA mutation exhibit variations in the growth form compared to susceptible biotypes of this weed.

Classified Plant Al-Dhahiriya in the South of Palestine

We studied plant species of Dhahiriya in the period between January to October 2021, and January to Jun 2024, due to the importance of plants in that vital part of Palestine, which is located in southern Palestine, including that region’s climate, and unique plants that represent of the Mediterranean region plants, North Africa, Sinai desert, Negev, Dead Sea, and Red Sea. It used the Braun-Blanquet (1979) method for the identification of plants. Moreover, Plants have been studied in Dhahiriya, located in southern Palestine. A total of 770 species from 70 families were identified, of which 86 (11.16%) are endemic. The plant families with the highest representation were Asteraceae (14.54%), Fabaceae (14%), Poaceae (7.41%), and Lamiaceae (5.19%). Regarding plant life forms, Therophytes account for 47%, Hemicryptophytes for 20.35%, Shrubs or Chamaephytes for 14.05%, and Trees or Phanerophytes for 9.05%, with a notable increase in spring.

Volume-based selection in Pinus pinaster Aiton breeding: evaluating resistance to Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle and wood properties

Key messageGenetic parameter estimates at age 12 years for trunk volume in Pinus pinaster displayed low to moderate heritability for growth and stem form, whereas wood properties showed high heritability. No correlation was detected between resistance to the nematode Bursaphelenchus xylophilus and growth, stem form, or wood properties. However, certain families stood out, showing favorable values across all traits, including resistance to the nematode.ContextThe breeding program for Pinus pinaster should advance towards a second-generation breeding population based on volume, stem form, and resistance to Bursaphelenchus xylophilus, with the challenge of incorporating novel traits of importance.AimsWe focused on assessing the genetic parameters of growth, stem form, wood properties, and resistance to B. xylophilus as well as exploring the relationship between these traits.MethodsWe evaluated 116 half-sib families at three ages (7, 12, and 17 years) in seven progeny trials established in 2005, analyzing growth, stem form, and wood traits. Resistance to B. xylophilus was assessed in 91 of the 116 half-sib families at age 2 by artificial inoculation tests under greenhouse conditions.ResultsAdvancing the selection age to 12 years proved to be feasible for volume selection in Galician P. pinaster. All traits, including resistance to B. xylophilus, showed potential for genetic improvement. Remarkably, resistance to B. xylophilus was not correlated to any other trait.ConclusionExcluding the most susceptible families to B. xylophilus from the Galician P. pinaster breeding program would not result in a significant decrease in volume, stem form, or wood properties.

Urban Cemeteries as Biodiversity Refuges: A Comparative Study of Plant Ecobiomorphs in Central Kazakhstan

Cemeteries are often overlooked in ecological studies, yet they represent unique urban microhabitats that contribute to the preservation of diverse plant species, including those adapted to various ecological niches. This study aimed to assess the species composition, ecological classifications, and abundance of vascular plants in the cemetery and surrounding areas to explore cemeteries’ role in conserving plant ecobiomorph diversity in arid climates. This study identified 79 plant species from 23 families within the cemetery compared with 31 species from 11 families in the surrounding area. The plant community in the cemetery was dominated by mesophytes, suggesting favorable and stable conditions for plant growth, while xerophytes were more common in the surrounding areas, indicating harsher, drier conditions. The diversity of plant life forms, including perennial herbs, shrubs, and trees, was significantly higher within the cemetery, indicating a more complex and resilient ecosystem. Our study demonstrates that cemeteries act as vital refuges for plant biodiversity. They offer significantly higher species diversity and more complex ecosystem structures compared with the surrounding areas. These findings emphasize the critical role cemeteries play in urban biodiversity conservation, particularly in increasingly arid environments.

Leaf architecture and functional traits for 122 species at the University of California Botanical Garden at Berkeley.

The dataset contains leaf venation architecture and functional traits for a phylogenetically diverse set of 122 plant species (including ferns, basal angiosperms, monocots, basal eudicots, asterids, and rosids) collected from the living collections of the University of California Botanical Garden at Berkeley (37.87° N, 122.23° W; CA, USA) from February to September 2021. The sampled species originated from all continents, except Antarctica, and are distributed in different growth forms (aquatic, herb, climbing, tree, shrub). The functional dataset comprises 31 traits (mechanical, hydraulic, anatomical, physiological, economical, and chemical) and describes six main leaf functional axes (hydraulic conductance, resistance and resilience to damages caused by drought and herbivory, mechanical support, and construction cost). It also describes how architecture features vary across venation networks. Our trait dataset is suitable for (1) functional and architectural characterization of plant species; (2) identification of venation architecture-function trade-offs; (3) investigation of evolutionary trends in leaf venation networks; and (4) mechanistic modeling of leaf function. Data are made available under the Open Data Commons Attribution License.

Patterns and Drivers of Pollen Temperature Tolerance.

Pollen, a pivotal stage in the plant reproductive cycle, is highly sensitive to temperature fluctuations, impacting seed quality and quantity. While the importance of understanding pollen temperature limits (Tmin, Topt, Tmax - collectively PTLs) is recognized, a comprehensive synthesis of underlying drivers is lacking. Here, we examined PTLs, correlating them with vegetative tissue thermotolerance and assessing variability at the intra- and interspecific levels across 191 species with contrasting phylogeny, cultivation history, growth form and ecology. At the species level, the PTLs range from 9.0 to 42.4°C, with considerable differences among individual species. Vegetative tissue showed greater tolerance to both low and high temperatures than pollen. A significant, though weak, correlation was observed between PTLs and leaf temperature tolerance. Pollen heat tolerance was independent of that in leaves and stems. The greatest intraspecific variability was observed in pollen cold tolerance (Tmin), followed by Topt and Tmax. Phylogenetic analysis revealed family-level conservation in all three pollen temperature tolerance measures. Climate emerged as a significant PTL driver of pollen cold tolerance, with species from colder and stable climates exhibiting enhanced cold tolerance. Cultivated and wild species did not differ in their pollen temperature tolerances. Herbaceous plants showed higher tolerance to high temperatures compared to shrubs and trees, potentially reflecting divergent thermal conditions during anthesis. This study provides the first formal analysis of complex relationships between pollen temperature limits, plant characteristics and environmental factors, providing crucial insights into climate change impacts on plant reproduction.

Kontribusi Mahasiswa dalam Merealisasikan Kreativitas Diri Melalui Model Pembelajaran Special Event di Politeknik Pariwisata Prima Internasional

Creativity is an activity that positively impacts human growth and development. One form of human growth and development is the output of creativity through an activity and a product. EPHICS emerged as a form of creativity from international prime tourism polytechnic students and involved students. Qualitative descriptive methods followed by observation and visualization of layouts assisted by the interview process and documentation to collect data related to research. As a result of this activity program, students make a field learning model that can continue to hone creativity and is expected to develop EPHICS even better. SWOT analysis and analysis of the concept of event implementation become the basis for the activity evaluation process. The evaluation results obtained after each activity is completed are used as material for improvement in the implementation of future EPHICS activities to make it even better.

Unraveling Magnet Structural Defects in Permanent Magnet Synchronous Machines—Harmonic Diagnosis and Performance Signatures

Rare-earth-based permanent magnets (PMs) have a vital role in numerous sustainable energy systems, such as electrical machines (EMs). However, their production can greatly harm the environment and their supply chain monopoly presents economic threats. Alternative materials are emerging, but the use of rare-earth PMs remains dominant due to their exceptional performance. Damage to magnet structure can cause loss of performance and efficiency, and propagation of cracks in PMs can result in breaking. In this context, prolonging the service life of PMs and ensuring that they remain damage-free and suitable for re-use is important both for sustainability reasons and cost management. This paper presents a new harmonic content diagnosis and motor performance analysis caused by various magnet structure defects or faults, such as cracked or broken magnets. The proposed method is used for modeling the successive physical failure of the magnet structure in the form of crack formation, crack growth, and magnet breakage. A surface-mounted permanent magnet synchronous motor (PMSM) is studied using simulation in Ansys Maxwell software (Version 2023), and different cracks and PM faults are modeled using the two-dimensional finite element method (FEM). The frequency domain simulation results demonstrate the influence of magnet cracks and their propagation on EM performance measures, such as stator current, distribution of magnetic flux density, back EMF, flux linkage, losses, and efficiency. The results show strong potential for application in health monitoring systems, which could be used to reduce the occurrence of in-service failures, thus reducing the usage of rare-earth magnet materials as well as cost.

Grassland albedo as a nature-based climate prospect: the role of growth form and grazing

Abstract Nature-based solutions for mitigating climate change focus largely on land management to reduce carbon emissions and enhance carbon sequestration. Tree planting, commonly advocated for carbon offset, threatens grassland biodiversity and may induce positive radiative forcing (warming) by lowering albedo. Before making decisions about land-use changes in grasslands, an understanding of the fine-scale albedo of grassy versus woody vegetation is needed. Existing satellite-based albedo products offer global coverage with temporally fine, but spatially coarse, resolution, whereas fine-scale in situ grassland albedo data are sparse. We examined the hypotheses that albedo varies seasonally between grass type patches, between shrub and grass patches, and with grazing at the patch scale. Using a tripod-mounted albedometer, we quantified albedo of seven distinct grassland patches in South Africa’s eastern Karoo during early and late dormancy and growing seasons. Patches included intensely-grazed grazing lawn (Cynodon dactylon), grazed and less-grazed red tussock grass (Themeda triandra), grazed and less-grazed white tussock grass (Eragrostis lehmanniana), shrub (Pentzia incana) encroached grass, and bare ground. Season influenced albedo in all patches and, additionally, we found strong differences for the same period between years due to varying rainfall and temperature patterns. For grass-dominated patches, albedo differences were most pronounced during early dormancy, likely due to an effect of grass inflorescences. Albedo of intensely-grazed grazing lawns was consistently higher than other patches, except during early dormancy when white tussock grass albedo was equally high. We found no albedo difference between grazed and less-grazed tussock patches of either red or white grass. Shrub-encroached patches exhibited consistently lower albedo than other patches. Our findings underscore the nuanced relationship between grassland patches and albedo, with shrub encroachment, proposed afforestation, and certain grasses possibly increasing warming potential through reduced albedo. As climate initiatives extend into grasslands, understanding these patterns is essential for climate change mitigation and grassland conservation.

Speciation and evolution of growth form in Adesmia D. C. (Dalbergieae, Fabaceae): the relevance of Andean uplift and aridification.

The Andean uplift and the concomitant aridification drove the rapid diversification of several plant lineages that were able to colonize warmer and drier habitats at low elevations and wetter and colder habitats at high elevations. These transitions may be facilitated by shifts in plant strategies to cope with drought and cold, which in turn can trigger episodes of accelerated species diversification. Here, we used four nuclear DNA markers to infer phylogenetic relationships of 80 Adesmia species of annuals, perennial herbs, shrubs and small shrubs that occur in Chile and Argentina. We reconstructed ancestral states for area, climatic niche and growth form to explore how Andean uplift and aridification promoted Adesmia diversification. We also performed logistic and linear regression analyses between different components of growth form (life span, woodiness and plant height) and climate. Finally, we estimated speciation rates across the phylogeny. Our results suggest that the ancestor of Chilean Adesmia was a perennial herb that probably originated in the high Andes of northern and central Chile. The low elevations of Central Chile were colonized in the late Miocene, whereas the high latitudes of Patagonia and the hyperarid coastal Atacama Desert were colonized repeatedly since Pliocene by lineages with different growth forms. Multiple and bidirectional transitions between annual and perennial habits and between herbaceous and woody habits were detected. These shifts were not correlated with climate, suggesting that the different growth forms are alternative and successful strategies to survive unfavorable seasons of both desert and high Andes. Net diversification analysis indicated a constant rate of diversification, suggesting that the high species diversity of Adesmia that occur in Chile is due to a uniform speciation process rather than to accelerated episodes of speciation.

Seagrass space occupation efficiency is key for their role as ecosystem engineers and ecological indicators

Studies for the preservation of seagrass beds biotopes have met difficulties in establishing appropriate methods assessing their health. We tested the efficiency of space occupation by seagrasses scattered worldwide (dgrass index), which proved to be dependent on clonal growth form and morphometric plasticity. dgrass correlated with the above-ground to below-ground biomass ratio. However, the latter was misleading when high ratios resulted from low below-ground biomass. Nutrient Posphate-limitations were revealed in situations of theoretical Nitrogen-limitation. Enhanced nutrient supply benefitted seagrasses only up to a threshold after which it became detrimental. Better nurtured, healthier meadows with denser canopies increased the organic matter in the sediment and had associated greater abundances of benthic macrofauna. Hence, seagrass biotopes could benefit from moderate anthropogenic nutrient additions. However, organic matter above ≈6% and/or reduced riverine discharges (dams upstream and climate-change-related droughts) were detrimental to healthy meadows, jeopardizing ecosystem services such as macrofauna abundances and carbon sinks.

Changes in Leaf Functional Traits with Leaf Age for Coexisting Woody Species in Temperature Forest of Northern China

Leaf-trait variation has traditionally been focused on both within and among species along environmental gradients, while leaf age has received less attention. By measuring leaf morphological, stomatal, and stoichiometric traits of 40 coexisting woody species in temperate forest in northern China, we analyzed their variation pattern and the correlations among different plant life forms and leaf age. We found that leaf age has significant effects on leaf functional traits. The young leaves of both shrub and tree species revealed a lower stoma density (SD) and a higher stoma length (SL), stoma width (SW), and leaf N content (LNC) than mature leaves. Shrub species have a higher SLA and SD than tree species for both young and mature leaves. The traits of young leaves generally revealed a higher variation than those of mature leaves. Although correlations between traits are similar between young leaves and mature leaves, the slopes of the SLA–SD and SD–LNC relationships were significantly affected by leaf age. These findings elucidate the adaptive changes of leaf traits during leaf maturation and underscore the trade-off between stomatal safety and efficiency, as well as the trade-off between leaf hydraulic and economic traits in temperate woody species during leaf development. We conclude that variation in leaf traits with age may play a potentially important role in understanding the ecological function of woody species in temperate forests.